Ashless dispersants

Abstract

According to the present invention, improved dispersants are provided which comprise adducts of (A) polymer-substituted mono- and dicarboxylic acid or anhydrides and (B) bis(para-amino cyclohexyl) methane oligomers, wherein the reactants are contacted in a reaction zone in the substantial absence of polar organic solvents.

We claim: 
     
       1. Dispersant adduct useful in lubricating oils comprising reaction products of (A) polymer-substituted mono- or dicarboxylic acid or anhydrides derived from the reaction of (i) polyolefin with (ii) monounsaturated carboxylic reactant and (B) bis (para-amino cyclohexyl) methane oligomers; said reaction being conducted in a manner and under conditions sufficient to formimide, amide or mixtures thereof. 
     
     
       2. The dispersant adduct according to claim 1 wherein the polymer comprises polybutylene. 
     
     
       3. The dispersant adduct according to claim 2 wherein the polymer comprises polyisobutylene. 
     
     
       4. The dispersant adduct according to claim 1 wherein the reactant (A) comprises a polymer-substituted succinic acid or anhydride. 
     
     
       5. The dispersant adduct according to claim 4 wherein reactant (A) is derived by the reaction of maleic anhydride and a polybutylene having a number average molecular weight of from about 1,300 to 3,000. 
     
     
       6. The dispersant adduct according to claim 1 wherein the reactant (B) contains from about 8 to 16 wt. % total N. 
     
     
       7. The dispersant adduct according to claim 1 wherein the dispersant adduct contains at least one primary or secondary amino group per molecule. 
     
     
       8. The dispersant adduct according to claim 7 wherein the dispersant adduct contains from 1 to 15 primary or secondary amine groups per molecule.